/**
 * 배송/화물 관리 서비스
 * 
 * 실제 데이터베이스 연동 시 필요한 메서드들을 미리 정의
 */

import pool from '../database/db';

export interface DeliveryItem {
  id: string;
  trackingNumber: string;
  customer: string;
  origin: string;
  destination: string;
  status: 'in_transit' | 'delivered' | 'delayed' | 'pickup_waiting';
  estimatedDelivery: string;
  delayReason?: string;
  priority: 'high' | 'normal' | 'low';
}

export interface CustomerIssue {
  id: string;
  customer: string;
  trackingNumber: string;
  issueType: 'damage' | 'delay' | 'missing' | 'other';
  description: string;
  status: 'open' | 'in_progress' | 'resolved';
  reportedAt: string;
}

export interface TodayStats {
  shipped: number;
  delivered: number;
}

export interface DeliveryStatusResponse {
  deliveries: DeliveryItem[];
  issues: CustomerIssue[];
  todayStats: TodayStats;
}

/**
 * 배송 현황 조회
 * 
 * TODO: 실제 DB 연동 시 구현 필요
 * - 테이블명: deliveries (배송 정보)
 * - 테이블명: customer_issues (고객 이슈)
 * 
 * 예상 쿼리:
 * SELECT * FROM deliveries WHERE DATE(created_at) = CURRENT_DATE
 * SELECT * FROM customer_issues WHERE status != 'resolved' ORDER BY reported_at DESC
 */
export async function getDeliveryStatus(): Promise<DeliveryStatusResponse> {
  try {
    // TODO: 실제 DB 쿼리로 교체
    // const deliveriesResult = await pool.query(
    //   `SELECT 
    //      id, tracking_number as "trackingNumber", customer, origin, destination,
    //      status, estimated_delivery as "estimatedDelivery", delay_reason as "delayReason",
    //      priority
    //    FROM deliveries 
    //    WHERE deleted_at IS NULL 
    //    ORDER BY created_at DESC`
    // );

    // const issuesResult = await pool.query(
    //   `SELECT 
    //      id, customer, tracking_number as "trackingNumber", issue_type as "issueType",
    //      description, status, reported_at as "reportedAt"
    //    FROM customer_issues 
    //    WHERE deleted_at IS NULL 
    //    ORDER BY reported_at DESC`
    // );

    // const statsResult = await pool.query(
    //   `SELECT 
    //      COUNT(*) FILTER (WHERE status = 'in_transit') as shipped,
    //      COUNT(*) FILTER (WHERE status = 'delivered') as delivered
    //    FROM deliveries 
    //    WHERE DATE(created_at) = CURRENT_DATE 
    //    AND deleted_at IS NULL`
    // );

    // 임시 응답 (개발용)
    return {
      deliveries: [],
      issues: [],
      todayStats: {
        shipped: 0,
        delivered: 0,
      },
    };
  } catch (error) {
    console.error('배송 현황 조회 실패:', error);
    throw error;
  }
}

/**
 * 지연 배송 목록 조회
 */
export async function getDelayedDeliveries(): Promise<DeliveryItem[]> {
  try {
    // TODO: 실제 DB 쿼리로 교체
    // const result = await pool.query(
    //   `SELECT * FROM deliveries 
    //    WHERE status = 'delayed' 
    //    AND deleted_at IS NULL 
    //    ORDER BY estimated_delivery ASC`
    // );
    
    return [];
  } catch (error) {
    console.error('지연 배송 조회 실패:', error);
    throw error;
  }
}

/**
 * 고객 이슈 목록 조회
 */
export async function getCustomerIssues(status?: string): Promise<CustomerIssue[]> {
  try {
    // TODO: 실제 DB 쿼리로 교체
    // const query = status
    //   ? `SELECT * FROM customer_issues WHERE status = $1 AND deleted_at IS NULL ORDER BY reported_at DESC`
    //   : `SELECT * FROM customer_issues WHERE deleted_at IS NULL ORDER BY reported_at DESC`;
    
    // const result = status 
    //   ? await pool.query(query, [status])
    //   : await pool.query(query);
    
    return [];
  } catch (error) {
    console.error('고객 이슈 조회 실패:', error);
    throw error;
  }
}

/**
 * 배송 정보 업데이트
 */
export async function updateDeliveryStatus(
  id: string, 
  status: DeliveryItem['status'],
  delayReason?: string
): Promise<void> {
  try {
    // TODO: 실제 DB 쿼리로 교체
    // await pool.query(
    //   `UPDATE deliveries 
    //    SET status = $1, delay_reason = $2, updated_at = NOW() 
    //    WHERE id = $3`,
    //   [status, delayReason, id]
    // );
    
    console.log(`배송 상태 업데이트: ${id} -> ${status}`);
  } catch (error) {
    console.error('배송 상태 업데이트 실패:', error);
    throw error;
  }
}

/**
 * 고객 이슈 상태 업데이트
 */
export async function updateIssueStatus(
  id: string, 
  status: CustomerIssue['status']
): Promise<void> {
  try {
    // TODO: 실제 DB 쿼리로 교체
    // await pool.query(
    //   `UPDATE customer_issues 
    //    SET status = $1, updated_at = NOW() 
    //    WHERE id = $2`,
    //   [status, id]
    // );
    
    console.log(`이슈 상태 업데이트: ${id} -> ${status}`);
  } catch (error) {
    console.error('이슈 상태 업데이트 실패:', error);
    throw error;
  }
}